Quadrifilar helix antenna for MIMO system

In this letter, the performance of using a meander line printed quadrifilar helix antenna (MPQHA) structure in a multiple-input-multiple-output (MIMO) system was investigated. It is known that MIMO systems can offer larger capacity than traditional systems, and can exploit transmit or receive diversity. An important parameter is the correlation between the adjacent channels, with a capacity increase for low correlation. It was found that the MPQHA offers low correlation between its individual elements, and has significant advantages in terms of size compared to an array of monopole antennas.